Skip to content

Author: Sima

Published on Leave a comment on Can Probiotics Prevent Sepsis in Babies?

Could something as simple as giving a probiotic and a sugar for 7 days prevent sepsis in babies? Sepsis is a life-threatening infection that is a HUGE problem in developing countries such as India. It is a major cause of death in babies throughout the world, even with antibiotic treatment. So this new research (done in India) finding that giving newborn babies a probiotic plus the sugar fructooligosaccharide (FOS) for only one week had the result of lowering the incidence of sepsis and death by 40%, and also infections is huge news. A game changer.

The researchers found that the strain given to the babies was very important. They first tried Lactobacillus GG and Lactobacillus sporogenes, but didn't have success. But a strain of Lactobacillus plantarum was amazingly effective. They gave it together with a sugar - fructooligosaccharide (FOS) - which together worked as a synbiotic. Synbiotics are combinations of probiotics with an FOS supplement that promotes growth and colonization of the beneficial bacteria. FOS (which is naturally found in breast milk and such plants as onion, chicory, garlic, asparagus, banana, artichoke, agave, leeks, wheat, barley), is food for the probiotic bacteria.

It must be pointed out that other studies have tried other probiotics in the prevention of sepsis, but have not been successful. Probiotics that did not work work in other studies were Streptococcus thermophilus, Bifidobacterium infantis, Bifidobacterium lactis, and Bifidobacterium breve. However, they did not also use prebiotic supplements (the FOS) - just the probiotic alone - and studied premature or low birth weight babies (while this study focused on healthy babies of approximately normal weight.) This is why research now needs to be done looking at other groups of babies. From Medical Xpress:

Study shows probiotics can prevent sepsis in infants

A research team at the University of Nebraska Medical Center College of Public Health has determined that a special mixture of good bacteria in the body reduced the incidence of sepsis in infants in India by 40 percent at a cost of only $1 per infant...... The special mixture included a probiotic called Lactobacillus plantarum ATCC-202195 combined with fructo-oligosaccharide (FOS), an oral synbiotic preparation developed by Dr. Panigrahi.

Probiotics are live bacteria and yeasts that are good for your health, especially your digestive system. Synbiotics are combinations of probiotics with an FOS supplement that promotes growth and sustains colonization of the probiotic strain. FOS, naturally found in breast milk and such plants as onion, chicory, garlic, asparagus, banana, artichoke and others, is food for the probiotic bacteria.

Sepsis is a severe complication of bacterial infection that results in around one million infant deaths worldwide each year, mostly in developing countries. It occurs when the immune system stops fighting germs and begins to turn on itself and can lead to tissue damage, organ failure and death. It is estimated that 40 percent of patients with severe sepsis in developing countries do not survive.

The team enrolled more than 4,500 newborns from 149 villages in the Indian province of Odisha and followed them for their first 60 days, the most critical period when they get sick and die. During their first days of life, the newborns were administered the oral preparation for seven days. Results of the randomized, double-blind, placebo-controlled study showed that sepsis and deaths in the first two months of infancy were reduced by 40 percent, more than twice the anticipated reduction of 20 percent. The synbiotic treatment also lowered respiratory tract infections. The effectiveness demonstrated in Dr. Panigrahi's study was so successful the study was halted early. 

An interesting article about this research from The Atlantic: At Last, a Big, Successful Trial of Probiotics

Published on Leave a comment on Probiotics Used In Successful Peanut Allergy Treatment

Amazing if this holds up in larger studies - a treatment for peanut allergy! As the researchers said -  the treatment (2 grams of peanut protein plus a specific strain of the probiotic Lactobacillus rhamnosus daily for 18 months) provided "persistent suppression of the allergic immune response to peanuts 4 years" after the treatment had ended This was a nicely done multi-year study in children - a randomised, double-blind, placebo-controlled trial (to eliminate biases).

The researchers also wrote in the Discussion section of the study: "PPOIT [combined probiotic and peanut oral immunotherapy] was associated with long-lasting peanut tolerance 4 years after stopping treatment. Two-thirds of PPOIT treated participants were able to continue regular peanut ingestion, and more than half were ingesting moderate to-large amounts of peanut on a regular basis, compared with only one (4%) of 24 placebo-treated participants. Allergic reactions from intentional peanut ingestion were uncommon and all reactions were mild, suggesting that those who achieved PPOIT-induced sustained unresponsiveness can safely continue peanut ingestion." In other words - WOW! (Other posts on peanut allergies - here and here, and earlier progress report of this study.) From Medical Xpress:

Australian researchers in peanut allergy breakthrough

Australian researchers have reported a major breakthrough in the relief of deadly peanut allergy with the discovery of a long-lasting treatment they say offers hope that a cure will soon be possible. In clinical trials conducted by scientists at Melbourne's Murdoch Childrens Research Institute, children with peanut allergies were given a probiotic along with small doses of a peanut protein over an 18-month period. When the experiment ended in 2013 some 80 percent of the kids were able to tolerate peanuts. The research, published Wednesday in medical journal The Lancet, found that four years on, about 70 percent could still eat peanuts without an adverse reaction.

"The importance of this finding is that these children were able to eat peanuts like children who don't have peanut allergy and still maintain their tolerant state, protected against reactions to peanut," lead researcher Mimi Tang said. "These findings suggest our treatment is effective at inducing long-term tolerance, up to four years after completing treatment, and is safe. Food allergy affects one in 20 children and about two in 100 adults, with seafood, cow's milk, eggs and peanuts among the most typical triggers. Peanuts are one of the most common foods to cause anaphylaxis, a potentially fatal allergic reaction.

The researchers said the Murdoch study provides the "strongest evidence yet that a cure may be possible for peanut allergy"..... Ten-year-old Olivia May suffered a reaction when she tried to eat a peanut butter sandwich seven years ago. "We visited the allergist the first time [and] he said 'sorry, you're going to have to go home and empty your pantry out, clear it of all nuts, anything with nuts in it'," Oliver's mother Tanya told the Australian Broadcasting Corporation. But after taking part in the trial, Oliva no longer suffers from her allergy.

Fifty-six children completed the study, with half receiving a placebo and half receiving the treatment, which encourages the immune system to develop a tolerance to the allergy. Researchers are now aiming to confirm the results with a larger study of the treatment they say "holds important implications for attacking the modern food allergy epidemic". [Original study.]

Published on Leave a comment on Is ‘Fat But Fit’ A Myth?

Is "fat but fit" a myth or true? The results of this study suggest that it is a myth. That there is a higher risk of coronary heart disease, and even if everything looks OK initially, it is associated with an eventual metabolic changes (and problems). Just wait a while - as can be seen in the results of this study that followed people from 8 European countries over many years (about 12.2 years). The study found that being normal weight and fit is best, and that "metabolically healthy" obese people were more likely to go on to develop metabolic abnormalities (and become metabolically unhealthy obese people) over the years. Metabolically unhealthy signs included high blood pressure, low HDL-cholesterol, and hyperglycemia (high blood sugar).

Bottom line: aim for normal weight for a lower risk of heart disease (and of course, be physically active and eat a healthy diet - fewer processed foods, and more fruits, vegetables, whole grains, seeds, nuts, and legumes). From Science Daily:

'Fat but fit' are at increased risk of heart disease

Carrying extra weight could raise your risk of heart attack by more than a quarter, even if you are otherwise healthy.Researchers have found that being overweight or obese increases a person's risk of coronary heart disease (CHD) by up to 28 per cent compared to those with a healthy body weight, even if they have healthy blood pressure, blood sugar and cholesterol levels.The findings add to a growing body of evidence that suggests being 'fat but fit' is a myth, and that people should aim to maintain a body weight within a healthy range.  ...continue reading "Is ‘Fat But Fit’ A Myth?"

Published on Leave a comment on Hair Dyes, Hair Relaxers, and Breast Cancer

There has long been concern over the chemicals in hair dyes and chemical hair straighteners or relaxers, and whether they are linked to various cancers. Studies have had mixed findings with regard to breast cancer, but a review paper concluded that there is evidence to support a role of hair product use in the risk of early onset breast cancer, especially in African-American women. Other studies found that long term users of dark hair dyes have a significantly increased risk of non-Hodgkin's lymphoma, multiple myeloma, and bladder cancer. 

A recent study done in the New York City and New Jersey area looked at both African-American women and white women and their use of various hair chemical products. They found that regularly chemically relaxing hair or dying hair dark brown or black is associated with an elevated risk of breast cancer in both African-American and white women. And women using both types of products had an even higher risk of breast cancer.From Medscape:

Dark Hair Dye and Chemical Relaxers Linked to Breast Cancer

African-American and white women who regularly chemically straighten their hair or dye it dark brown or black have an elevated risk of breast cancer, new research suggests. The study of 4,285 African-American and white women was the first to find a significant increase in breast cancer risk among black women who used dark shades of hair dye and white women who used chemical relaxers.

Black women who reported using dark hair dye had a 51 percent increased risk of breast cancer compared to black women who did not, while white women who reported using chemical relaxers had a 74 percent increased risk of breast cancer, the study found. The risk of breast cancer was even higher for white women who regularly dyed their hair dark shades and also used chemical relaxers, and it more than doubled for white dual users compared to white women who used neither dark dye nor chemical straighteners.

The study included adult women from New York and New Jersey, surveyed from 2002 through 2008, who had been diagnosed with breast cancer, plus women of similar age and race but without a history of cancer.....While the vast majority - 88 percent - of blacks had used chemicals to relax their hair, only 5 percent of whites reported using relaxers. For dark hair dye, the numbers flipped, though the differences were not as dramatic. While 58 percent of whites said they regularly dyed their hair dark shades, only 30 percent of blacks did.

The most striking results showed increased risk in the minority of black women who used dark hair dye and white women who used chemical relaxers. Black women who used chemical straighteners and white women who used dark hair dyes were also at higher risk for breast cancer, but that might have been due to chance. James-Todd said that because so many of the black women used chemical relaxers and so many of the white women used dark hair dye, links would have been hard to detect. There’s no reason to believe that chemical relaxers and hair dyes would increase the risk for women of one race and not of another, she said. 

Previous studies have shown that long-term users of dark dyes have a four-fold increased risk of fatal non-Hodgkin’s lymphoma and fatal multiple myeloma, the authors write. Prior research also has associated dark hair dye use with an increased risk of bladder cancer. A 2016 report from the U.S. Centers for Disease Control and Prevention found that breast cancer rates are generally similar for black and white women, at around 122 new cases for every 100,000 women per year, although black women with the disease are more likely to die from it.  [Original study.]

Published on Leave a comment on Did Your Cardiologist Discuss Nutrition With You?

So, how many of you have had doctors discuss nutrition with you? How about your cardiologist? "No"...many of you answer. Well, that shouldn't be surprising according to a new survey of 930 cardiologists, cardiologists-in-training, and cardiovascular health professionals. Among practicing cardiologists, fully 90% reported that they received either no or minimal nutrition education during their cardiology training. And currently there is no requirement that nutrition needs to be taught in cardiology training. Most also reported that they spend less than 3 minutes discussing nutrition per appointment. What does that really mean? Is it just a few words like: lose weight, eat better, and eat less salt? That's not enough to be real nutrition advice.

Why is nutrition important? Among the top 17 risk factors, poor diet quality has been identified by the US Burden of Disease Collaborators as the leading cause of premature deaths and disability in the United States. Heart health is influenced by the diet. Many studies have shown that people following such healthy diets as the Mediterranean diet (with an emphasis on fruits, vegetables, whole grains, seeds, nuts, legumes, and olive oil) have a significantly lower incidence of heart disease and major cardiovascular events (especially strokes). One recent study (an analysis of other studies) linked eating 8 to 10 portions of fruits and vegetables daily with a lower risk of early death, cancer, heart disease, and stroke. From Medscape:

Cardiologists Are Hungry for Knowledge on Nutrition

Hello. My name is Dr Stephen Devries and I'm a cardiologist and executive director of the nonprofit Gaples Institute for Integrative Cardiology. It's a pleasure to have an opportunity to share with you some interesting findings related to a new study I was involved in regarding nutrition education in cardiology. I'm sure you are aware that patients increasingly want to take more charge of their own health. In order to do so, they are asking their doctors more questions about nutrition. But how prepared are physicians to address those questions? Specifically, we asked: How prepared are cardiologists to deal with nutrition questions in their own practice?

In order to get at that question, my colleagues and I, members of the Nutrition Working Group of the American College of Cardiology, surveyed[1] over 900 practicing cardiologists, cardiologists-in-training, and cardiovascular health professionals and asked them a wide range of questions relating to their experience with nutrition education, their attitudes about nutrition and practice, and a little bit about their own personal nutrition habits.

What did we find? Among practicing cardiologists, fully 90% reported that they received either no or minimal nutrition education during their cardiology training. When we inquired a bit about their attitudes regarding nutrition and practice, 95% of cardiologists reported that they believed it was their personal responsibility to deliver at least basic nutrition education to their patients. We were a bit surprised. We had wondered whether cardiologists felt that it was someone else's job to do; but no, they felt that it was their own personal responsibility to at least deliver basic diet counseling to their patients.

We then asked cardiologists about their own personal health habits and inquired about their personal intake of vegetables and fruit. We found that only 20% of practicing cardiologists reported eating a total of five or more servings of vegetables and fruit per day. That is an important finding, not only because it speaks to opportunities to improve cardiologists' own health, but also because there are data[2] showing that physicians who adopt healthy lifestyle practices are more likely to counsel patients to do so as well.

Where do we go from here? It's paradoxical that nutrition and lifestyle are identified in many of our clinical care guidelines as the foundations of good cardiovascular care, yet how can our cardiologists implement those guidelines without receiving adequate nutrition training? Obviously, we need to address that problem by providing meaningful nutrition education in all phases of medical training, beginning in medical school through internal medicine residency, and extending into cardiovascular training itself. Currently there is no requirement that nutrition needs to be taught in cardiology training—and that needs to change. We also should include more nutrition content on board exams so that there will be additional motivation to teach nutrition to help pass the exam.

2

Published on 2 Comments on Higher Cadmium Levels and Endometrial Cancer

Image result for lobster meal wikipedia A recent study provided evidence that higher levels of cadmium in women may increase the risk of endometrial cancer. Endometrial cancer is the fourth most common cancer in women, and it occurs primarily in postmenopausal women. Endometrial cancer is associated with estrogen exposure (for example, being obese, and also from external or environmental sources of estrogen).

Cadmium is a metal commonly found in foods such as kidneys, liver, and shellfish, but also tobacco (cigarette smoking). Cadmium is toxic, it accumulates in the body, it is an estrogen-mimicking chemical, and it is associated with several hormone-dependent cancers. The researchers found that a doubling of cadmium exposure (as compared to those with low levels) was associated with a 22% increased risk of endometrial cancer.  Bottom line: Go ahead and enjoy these foods, but try to eat foods with naturally high levels of cadmium in moderation - such as shellfish, kidneys, and liver. From Science Daily:

Increased endometrial cancer rates found in women with high levels of cadmium

More than 31,000 new cases of endometrial cancer are expected to be diagnosed in 2017. Through a five-year observational study recently published in PLOS One, researchers at the University of Missouri found that women with increased levels of cadmium -- a metal commonly found in foods such as kidneys, liver and shellfish as well as tobacco -- also had an increased risk of endometrial cancer. It's an observation the researchers hope could lead to new treatments or interventions to prevent the fourth most common cancer in women.

"Cadmium is an estrogen-mimicking chemical, meaning it imitates estrogen and its effects on the body," said lead author Jane McElroy, Ph.D., associate professor in the Department of Family and Community Medicine at the MU School of Medicine. "Endometrial cancer has been associated with estrogen exposure. Because cadmium mimics estrogen, it may lead to an increased growth of the endometrium, contributing to an increased risk of endometrial cancer."

The research team partnered with cancer registries in Missouri, Arkansas and Iowa to identify cases of endometrial cancer. The team enrolled 631 women with a history of endometrial cancer in the study and 879 women without a history of the cancer to serve as a control group. The participants were asked to complete a survey of more than 200 questions about risk factors potentially associated with endometrial cancer. Once they completed the questionnaire, participants were sent a kit to collect urine and saliva samples. Through tests conducted at the MU Research Reactor, the samples were analyzed for cadmium levels.

While more research is needed to better understand the risks associated with cadmium, researchers say there are steps individuals can take to limit their cadmium-associated cancer risks. "We all have cadmium present in our kidneys and livers, but smoking has been shown to more than double a person's cadmium exposure," McElroy said. "Also, we recommend being attentive to your diet, as certain foods such as shellfish, kidney and liver can contain high levels of cadmium. You don't necessarily need to cut these from your diet, but eat them in moderation. This is especially true if women have a predisposition to endometrial cancer, such as a family history, diabetes or obesity." [Original study.]

Published on Leave a comment on Exercise Linked To Lower Mortality After Prostate Cancer Diagnosis

Another reason exercise is good for you: A large study found that men who exercise after a diagnosis of prostate cancer (but which is not metastatic) had a lower risk of dying from prostate cancer - as compared to those men who don't exercise.

So get out there and do something that gets you moving - and yes, walking is an exercise (Note: 1 mile = 20 minutes of walking, thus 3 miles = 1 hour).

In this study the average age at diagnosis was 71, but studies find that exercise has numerous benefits at all ages. Some doctors even think of exercise as "anticancer therapy" (here, here). Also, exercise has anti-inflammatory benefits, and current thinking is that chronic inflammation is linked to cancer.

The American Cancer Society in its cancer prevention guidelines recommends that adults should be physically active, and get at least 150 minutes of moderate physical activity or 75 minutes of vigorous intensity activity each week (or a combination of these), preferably spread throughout the week.

From Medscape: Exercise Linked to Lower Mortality With Early Prostate Cancer

Men with nonmetastatic prostate cancer may have longer survival the more they exercise, a recent study suggests. For these men, regular moderate or vigorous physical activity was associated with 31 percent to 37 percent lower likelihood of death during the study, compared to more modest amounts of exercise.

“This confirms and expands on previous work that shows an inverse association between recreational physical activity after diagnosis and risk of prostate cancer-specific mortality,” said lead study author Ying Wang of the American Cancer Society in Atlanta, Georgia, in email to Reuters Health.

Wang and colleagues pulled data from a large, long-term study group established by the American Cancer Society in 1992, focusing on 7,000 men who were diagnosed with prostate cancer between 1992 and 2011. The average age at cancer diagnosis was 71, and there were 2,700 deaths through 2012, including 450 due to prostate cancer and 750 due to heart disease. The average time from diagnosis to death was about eight years for those who died from cancer and 10 years for those who died from other causes.

Men who were more active before diagnosis were more likely to have lower-risk cancer tumors and a history of prostate screenings. They were also leaner, more likely to be nonsmokers and vitamin users and they ate more fish. Both before and after diagnosis, walking accounted for 73 percent of the physical activity that men did, followed by 10 percent for cycling and 5 percent for aerobic exercise, according to the report online now in European Urology.

Based on exercise levels before diagnosis, moderate to vigorous exercise, including walking, was linked to lower risk of death from prostate cancer, but only for men with lower-risk tumors. But after the diagnosis, the same levels of exercise were linked to lower risk of death from prostate cancer for all men, although the apparent benefit of walking was no longer statistically meaningful. [Original study.]

Published on Leave a comment on Flame Retardants And Reduced IQ In Children

A new study that analyzed other studies (a meta-analysis) found that the class of flame retardant chemicals called PBDEs (commonly found in furniture and household products) has an effect on children's intelligence, so that it results in a loss of IQ points. Most of the studies looked at the child's exposure to flame retardants during pregnancy and then later IQ. They found that the child's IQ was reduced by 3.70 points for each ten-fold increase in flame retardant levels (thus, the higher the PBDE levels, the greater the effect on the child's IQ). This is of concern because flame retardants are in so many products around us, both in and out of the home. Older flame retardants (PBDEs) were phased out by 2013, but it turns out that the newer replacements (TBB and TBPH, including Firemaster 550) also get into people and also have negative health effects.

More and more research is finding health problems with flame retardants because they are "not chemically bound" to the products in which they are used - thus they escape over time. and get into us via the skin (dermal), inhalation (from dust), and ingestion (from certain foods and dust on our fingers). And because flame retardants are persistant, they bioaccumulate (they build up over time). They can be measured in our urine and blood. Evidence suggests that flame retardants may be endocrine disruptors, carcinogenic, alter hormone levels, decrease semen quality in men, thyoid disruptors, and act as developmental neurotoxicants (when developing fetus is exposed during pregnancy)  so that children have lowered IQ and more hyperactivity behaviors.

Where are flame retardants found? All around us, and in us. They are so hard to avoid because they're in electronic goods, in upholstered furniture, polyurethane foam, carpet pads, some textiles, the foam in baby items (car seats, bumpers, crib mattresses, strollers,nursing pillows, etc.), house dust, building insulation, and on and on. What to do? Wash hands before eating. Try to use a vacuum cleaner with a HEPA filter. Try to avoid products that say they contain "flame retardants". Only buy upholstered furniture with tags that say they are flame retardant free. The California Childcare Health Program has an information sheet on how to lower exposure to fire retardants. From Medical Xpress:

Flame retardant exposure found to lower IQ in children

A hazardous class of flame retardant chemicals commonly found in furniture and household products damages children's intelligence, resulting in loss of IQ points, according to a new study by UC San Francisco researchers. The study, published Aug. 3, 2017, in Environmental Health Perspectives, included the largest meta-analysis performed on flame retardants to date, and presented strong evidence of polybrominated diphenyl ethers' (PBDE) effect on children's intelligence. Despite a series of bans and phase-outs, nearly everyone is still exposed to PBDE flame retardants, and children are at the most risk," said UCSF's Tracey Woodruff, professor in the Department of Obstetrics, Gynecology and Reproductive Sciences..... 

The findings go beyond merely showing a strong correlation: using rigorous epidemiological criteria, the authors considered factors like strength and consistency of the evidence to establish that there was "sufficient evidence" supporting the link between PBDE exposure and intelligence outcomes. Furthermore, a recent report by the National Academies of Sciences endorsed the study and integrated evidence from animal studies to reach similar conclusions that PBDEs are a "presumed hazard" to intelligence in humans.

Researchers examined data from studies around the world, covering nearly 3,000 mother-child pairs. They discovered that every 10-fold increase in a mom's PBDE levels led to a drop of 3.7 IQ points in her child." "Many people are exposed to high levels of PBDEs, and the more PBDEs a pregnant woman is exposed to, the lower her child's IQ," said Woodruff. "And when the effects of PBDEs are combined with those of other toxic chemicals such as from building products or pesticides, the result is a serious chemical cocktail that our current environmental regulations simply don't account for." The researchers also found some evidence of a link between PDBE exposures and attention deficit hyperactivity disorder (ADHD), but concluded that more studies are necessary to better characterize the relationship.

PBDEs first came into widespread use after California passed fire safety standards for furniture and certain other products in 1975. Thanks to the size of the Californian market, flame retardants soon became a standard treatment for furniture sold across the country..... Mounting evidence of PDBEs' danger prompted reconsideration and starting in 2003 California, other states, and international bodies approved bans or phase outs for some of the most common PBDEs. PBDEs and similar flame retardants are especially concerning because they aren't chemically bonded to the foams they protect. Instead, they are merely mixed in, so can easily leach out from the foam and into house dust, food, and eventually, our bodies. [Original study.]

Published on Leave a comment on Foxes May Help Keep Tick Numbers Down

  Finally some good news regarding ticks and the diseases they can transmit to humans. Currently ticks in the US are known to transmit at least 14 diseases, including Lyme disease. But a recent study done in the Netherlands found that the presence of predators such as foxes resulted in mice and voles having fewer ticks on them. A really big reduction in both tick numbers and the percentage of ticks infected with a disease. The researchers  thought that this was due to the mice and voles being less active when predators were nearby, and also that mice and voles that did venture further were preyed upon and eaten by the predators. So be happy if you see foxes in your neighborhood - they're beneficial. Excerpts from the NY Times:

Lyme Disease’s Worst Enemy? It Might Be Foxes

It is August, the month when a new generation of black-legged ticks that transmit Lyme disease and other viruses are hatching. On forest floors, suburban estates and urban parks, they are looking for their first blood meal. And very often, in the large swaths of North America and Europe where tick-borne disease is on the rise, they are feeding on the ubiquitous white-footed mice and other small mammals notorious for harboring pathogens that sicken humans.

But it doesn’t have to be that way. A new study suggests that the rise in tick-borne disease may be tied to a dearth of traditional mouse predators, whose presence might otherwise send mice scurrying into their burrows. If mice were scarcer, larval ticks, which are always born uninfected, might feed on other mammals and bird species that do not carry germs harmful to humans. Or they could simply fail to find that first meal. Ticks need three meals to reproduce; humans are at risk of contracting diseases only from ticks that have previously fed on infected hosts.

For the study, Tim R. Hofmeester, then a graduate student at Wageningen University in the Netherlands and the lead researcher of the study, placed cameras in 20 plots across the Dutch countryside to measure the activity of foxes and stone martens, key predators of mice. Some were in protected areas, others were in places where foxes are heavily hunted. Over two years, he also trapped hundreds of mice — and voles, another small mammal — in the same plots, counted how many ticks were on them, and tested the ticks for infection with Lyme and two other disease-causing bacteria. To capture additional ticks, he dragged a blanket across the ground.

In the plots where predator activity was higher, he found only 5 to 10 percent as many newly hatched ticks on the mice as in areas where predators were scarcer. Thus, there would be fewer ticks to pass along pathogens to the next generation of mice. In the study, the density of infected “nymphs,” as the adolescent ticks are called, was reduced to 6 percent of previous levels in areas where foxes were more active.“The predators appear to break the cycle of infection,’’ said Dr. Hofmeester, who earned his Ph.D. after the study.

Interestingly, the predator activity in Dr. Hofmeester’s plots did not decrease the density of the mouse population itself, as some ecologists had theorized it might. Instead, the lower rates of infected ticks, Dr. Hofmeester suggested in the paper, published in Proceedings of the Royal Society B, may be the result of small mammals curtailing their own movement when predators are around. [Original study.]

Published on Leave a comment on Vitamin D, Breast Cancer, and Melanoma

Two more studies found that higher levels of vitamin D in the blood are associated with better health outcomes - one study found a lower risk of breast cancer, especially among postmenopausal women, and in the other - better outcomes after a metastatic melanoma diagnosis.

The breast cancer study suggested that a fairly high blood level of vitamin D (25(OH)D serum level>38.0 ng/mL) was associated with a lower risk of breast cancer. But overall they found that women supplementing with vitamin D (more than 4 times a week) at any dose had a lower risk of breast cancer over a 5 year period than those not supplementing with vitamin D. From Environmental Health Perspectives:

Serum Vitamin D and Risk of Breast Cancer within Five Years

Vitamin D is an environmental and dietary agent with known anticarcinogenic effects, but protection against breast cancer has not been established. We evaluated the association between baseline serum 25-hydroxyvitamin D [25(OH)D] levels, supplemental vitamin D use, and breast cancer incidence over the subsequent 5 y of follow-up. From 2003-2009, the Sister Study enrolled 50,884 U.S. women 35-74 y old who had a sister with breast cancer but had never had breast cancer themselves. Using liquid chromatography-mass spectrometry, we measured 25(OH)D in serum samples from 1,611 women who later developed breast cancer and from 1,843 randomly selected cohort participants.

We found that 25(OH)D levels were associated with a 21% lower breast cancer hazard (highest versus lowest quartile). Analysis of the first 5 y of follow-up for all 50,884 Sister Study participants showed that self-reported vitamin D supplementation was associated with an 11% lower hazard. These associations were particularly strong among postmenopausal women.

In this cohort of women with elevated risk, high serum 25(OH)D levels and regular vitamin D supplement use were associated with lower rates of incident, postmenopausal breast cancer over 5 y of follow-up. These results may help to establish clinical benchmarks for 25(OH)D levels; in addition, they support the hypothesis that vitamin D supplementation is useful in breast cancer prevention.

The first sentence in the melanoma study lays out what is widely known: "Vitamin D deficiency (≤20 ng/mL) is associated with an increased incidence and worse prognosis of various types of cancer including melanoma." Studies show that the relationship between vitamin D, sunlight exposure, and melanoma is complicated in a number of ways, including: sun exposure may be associated with increased survival in patients with melanoma. which may mean that vitamin D has a protective role in patients with melanoma. Several studies suggest that vitamin D may delay melanoma recurrence and improve overall prognosis. The study also found that metastatic melanoma patients with vitamin D deficiency who are unable to or don't raise their vitamin D blood levels (25(OH)D3) have a worse outcome compared to those who are are able to markedly increase (by greater than >20 ng/mL) their 25(OH)D3 levels. From Oncotarget:

Vitamin D deficiency is associated with a worse prognosis in metastatic melanoma

Vitamin D deficiency (≤20 ng/mL) is associated with an increased incidence and worse prognosis of various types of cancer including melanoma. A retrospective, single-center study of individuals diagnosed with melanoma from January 2007 through June 2013 who had a vitamin D (25(OH)D3) level measured within one year of diagnosis was performed to determine whether vitamin D deficiency and repletion are associated with melanoma outcome.

A total of 409 individuals diagnosed with histopathology-confirmed melanoma who had an ever measured serum 25(OH)D3 level were identified. 252 individuals with a 25(OH)D3 level recorded within one year after diagnosis were included in the study .... A worse melanoma prognosis was associated with vitamin D deficiency, higher stage, ulceration, and higher mitotic rate. In patients with stage IV metastatic melanoma, vitamin D deficiency was associated with significantly worse melanoma-specific mortality. Patients with metastatic melanoma who were initially vitamin D deficient and subsequently had a decrease or ≤20 ng/mL increase in their 25(OH)D3 concentration had significantly worse outcomes compared to non-deficient patients who had a >20 ng/mL increase. Our results suggest that initial vitamin D deficiency and insufficient repletion is associated with a worse prognosis in patients with metastatic melanoma.